Porous stopper and method of making same



Patented Jan. 22, 1924.

UNITED STATES 1,481,505 PATENT OFFICE.

MAURICE F. GRASS, F CLEVELAND; OHIO, ASSIGNOR TO THE GRASSELLI CHEMI I CAL COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

' POROUS STOPPER AND METHOD OF MAKING- SAME.

Application filedOctobei 1, 1921. senar No. 504,605.

To (all whom itmag concern;

.Be it known that, I, MAURICE F. 'CRAss, a citizen of the United States, and a resident of East Cleveland, county of Cuyahoga, and State of Ohio, have invented a new and useful Improvement in Porous "Stoppers and Methods of Making Same, of which the following is a specification, the principle of the invention being herein explained and the best mode in which I have contemplated applying that principle, so as to distinguish it from other inventions.

The present invention relates to an improved stopper for use in the carboys or bottles which are used for the purpose of containing acids, and also to a method of p making such improved stopper.

In the shipment of acids large bottles or carboys are used which are of acid resistant material, usually glass, and in the past it has been the custom to close these bottles with glass or porcelain stoppers which are seated against the upper surface-of the neck of the bottle with some type of compressi-ble washer. The objection to the use of either glazed, vitrified or semi-vitrified earthenware or glass stoppers is that both are impenetrable to gas and liquids so that if the acid in the bottles becomes heated and partially volatilized there is no escape for this gas pressure, and sometimes the bottles are burst. The use of small vents in the stoppers has been suggested to permit the escape of gas, but the 5 objection to this construction is that the bottles are sometimes laid on their sides so that the acid contacts the stopper and would flow out through any vent that might be formed therein. To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawing and the following description set forth in detail one method and one product exemplifying my invention, such disclosed procedure and product constituting, however, but one of various applications of the principles of my invention.

In said annexed drawing Fig. 1 is a side elevation of the neck of an acid carboy closed by means of my improved stopper; and Fig. 2 is a side eleva- 5 tion partially in section of the stopper.

The usual acid containers are. large glass bottles-1, (see Fig. 1) having a relatively small neck 2, in opposite sides of which are formed recesses 3 for receiving the ends of a stopper-closing device which consists of two wires Sand 6, each bent into semicircular form, the wire 5 having inturned ends which are received in the recesses 3, and the wires 6 being pivotally connected to the wire 5 at points adjacent to the ends of the latter.

My improved stopper is shown in posi tion in the bottle 1, this stopper 8 consisting of a head portion 9 and a smaller cylindrical body portion 10, which fits loosely into the open neck 2 of the bottle. The under surface 11 of the head portion is, formed smooth and is seated against a compressible washer 12 of asbestos or other material, which in turn rests upon the upper edge ofthe bottle neck 2. After the stopper is placed in position the wire 5 is swung up into one of the two intersecting grooves13 or 14;, which extend over the top of the head 9, and the wire 6 is then pressed downward against the neck of the bottle, thus pulling down the wire 5 and securely locking the stopper against the neck of the bottle. This action also slightly compresses the washer 12 and effectively seals v the bottle. I

My improved stopper is first made by intimately mixing finely ground stoneware or earthenware clay, that is clay of the character that is used for making stone or earthenware, and a suitable amount of a combustible material, such as sawdust, straw, shavings or the like, which is first also brought to a very finely divided condition. This mixture is then tempered, ground and mixed in clay chaser mills after which it is molded into articles of the desired form and is fired, the firing process burning out all of the combustible material and leaving an innumerable number of very fine openings or voids throughout the stopper so that the stopper is porous, and is capable of permitting the passage of gas therethrough. The clay and combustible material may be mixed together in various proportions, the determining factor bein the brittleness which is imparted to the finished stopper by the use of too great amount of combustible material or improper firing or burning. The stoppers must not be too brittle or they will break readily. The clay that is mixed with the combustible material must be of such nature as is employed in making acid proof chemical stoneware or earthenware, so there fore it must be acid proof in this that it does not disintegrate through acid action.

In Fig. 2 I have shown the very fine voids 15 which are distributed throughout the entire body of the stopper, and'which permit the flow of gas therethrough, in the eventthat any considerable gas pressure is attained in the carboy. At the same time the stoppers are suificiently solid and acid proof so that acid will not leak through, although if the stopper is held in contact with the acid for any considerable period it will become saturated with acid and a slight amount will of course be vaporized from the outer side of the stopper which is in contact with the open air. Even when the stopper is saturated with acid, if anyconsiderable gas pressure is built up within the carboy this gas pressure will vent the acid in the stopper and will itself escape to the atmosphere through the interstices of the stopper without injury, either to the stopper or carboy.

It is of course immaterial as to the exact form in which my stopper may be made, and

I therefore particularly point out and distinctly claim as my invention 1. In a method of makinlg porous stoppers, the steps which consist in intimately mixing finely divided acid-resisting material with finely divided combustible material, molding the mixture to the desired shape, and then firing the same, whereby the combustible material is removed from the mixture.

2. In a method of making porous stoppers, the steps which consist in intimately mixing finely divided acid-resisting material with a small amount of fine sawdust or other combustible material, molding such mixture to the desired shape, and then firing the same, whereby the sawdust or other combustible material is burned and the material left in a porous condition.

3. In a method of making porous stop pers, the steps which consist in intimately mixing finely divided acid proof stoneware or earthenware clay with a small amount of fine sawdust or other combustible material, molding such mixture to the desired shape, and then firing the same, whereby the sawdust is burned and the material left in a hard porous acid proof condition.

4:. A porous stopper consisting of hardburned, acid-resisting clay, such stopper being resistant to the passage of liquid but being sufliciently porous to permit the passage of gas 'therethrough.

5. A stopper. consisting of acid-resisting material non-swellableupon the action of liquid and provided throughout its body with interstices through which gas formed in a'container may pass, the porosity of said stopper being s'ufiiciently restricted to resist the leakage of liquid therethrough'.

Signed by me, this 24 day of September,

MAURICE F. GRASS. 

